EL 6

Question 1

what is the equation to involving moles, mass and molar mass

Answer 1

mass = moles x molar mass
m(g) = n x Mr
(massive Mr mole)
n = m/Mr

Question 2

what is the relative formula mass (RFM)

Answer 2

the sum of all of the relative atomic masses of the elements in the substance

Question 3

what is the empirical formula

Answer 3

the simplest whole number ratio of atoms in a substance

Question 4

what is the molecular formula

Answer 4

the specific number of atoms found in a substance

Question 5

what are the two equations to work out percentage yield

Answer 5

% yield = actual amount in mol/ maximum theoretical amount in mol x 100
% yield = actual amount in g/maximum theoretical amount in g x100
both figures being used are of product
(actual amount in … of product and theoretical amount in … of product)

Question 6

when can you use a 1/2 when balancing equations

Answer 6

when dealing with diatomic elements such as O2